Look up purchase for specific party?

I'm new to iMIS and have been reading to find out how to look up a purchase for a specific party.

I'll have an email address from which I believe I can look up the party using an email address as per https://developer.imis.com/reference/find-party-using-filter-operator. E.g. api/party?email=eq:[email protected]

Then once I have the party ID I want to see if that party made a specific purchase. I expect I'd be using the api/Invoice endpoint as per https://developer.imis.com/reference/invoice#getinvoice but I don't see how I can filter by the party I'd previously looked up. I only want invoices from a single party.